As OpenAI prepares to open up ad sales to more marketers next month, it is trying to address what some advertisers say was lacking in the initial ad sales offering. Among other things, the ChatGPT creator is planning to streamline the process of ad buying, either in partnerships with ad tech firms or with its own ad management system. So far, advertisers that bought the first ad campaigns on ChatGPT have said that the process was low tech and that they haven’t received much data showing if their ads worked. Two executives at agencies working with early ChatGPT advertisers said they haven’t yet been able to prove the ads have driven any measurable business outcomes for their clients.